Dye from cotton-seed oil.



r'rnn ST TES EDGAR SIDDONS lVILSON, OF STROUD, AND EBENEZER STEVART, OF LONDON, ENGLAND.

DYE FROM COTTON-SEED OIL.

SPECIFICATION forming part of Letters Patent No. 640,061, dated December 26, 1899.

Application filed December 15, 1897. Serial No- 662,055. (No specimens.)

To all whom it may concern.-

Be it known that we, EDGAR SIDDONS WIL- soN, residing at Stroud, and EBENEZER STEW- ART, residing at London, England, subjects of the Queen of Great Britain, have invented new and useful Improvements in the Separation and Purification of Coloring-Matter from Crude Cotton-Seed Oil, (for which we have obtained a patentin Great Britain, No. 24,418, bearing date December 20, 1895; in France, No. 261,457, bearing date November 20, 1896, and in Egypt, No. 56, hearing date May 23, 1897,) of which the following isaspecification.

In refining crude cotton-seed oil by alkaline solutions-such, for example, as caustic soda or mono-carbonate of soda-with or without the addition of a soluble sulphite, a coloringmatter is removed from the oil which has not hitherto been found of much value, owing to its admixture with fatty matter and other impurities. We have found that by suitable treatment impurities can be removed from the coloring-matter and the latter rendered more suitable for use.

In carrying out our invention we take the alkaline liquor separated from the oil and containing the said coloring-matter and impurities and treat it by the process known to chemists as fractional precipitation, using for this purpose certain earthy salts, such as the chlorides of magnesium or calcium, sulphate of magnesia, or any of the salts of metallic bases, which, with the fatty acids removed from the oil by the said alkalineliquor, produce insoluble or not easily soluble soaps. The fatty acids, resinous matter, and other impurities are by this means Wholly or partly got rid of, and to the residual liquor, which contains the coloring-matter, is added hyd rochloric or sulphuric acid or any acid which will combine withthe alkali or decompose alkaline carbonate or soluble sulphite and precipitate the said coloring -matter. The coloring-matter precipitated as a flocculent precipitate is collected for use preferably in a pasty condition.

As an example of the application of ourinvention we give the following: Two thousand two hundred gallons of crude cottonseed oil are agitated in a suitable tank with six hundred gallons of a solution of soda crystals containing from one-quarter to one-half a pound of crystals to the gallon. We have found that the coloringmatter undergoes deterioration during this process if the temperature is allowed to reach the boiling-point, (212 Fahrenheit,) and we therefore prefer to use a refining solution of the above or other convenient strength at a temperature of about 120 to 130 Fahrenheit. After the oil and alkaline liquor have been kept in agitation for the time necessary to remove the coloring-matter the contents of the tank are allowed to separate by subsidence or are made to separate by any known methods and the liquor, 'which is of a deep brown color, is drawn off. The brown liquor is then mixed with a solution of magnesium or cal sium chloride, so that from one-half to one part, by weight, of the salt is added to one hundred parts, by weight, of the liquor. The mixture of liquor and salt solution is then raised to the boiling-point and kept boiling till the separation of the dark, insoluble, or not easily soluble mixture of soap and other impurities is complete. The hot liquor,which now contains the improved coloring-matter, is then allowed to remain at rest and is drawn off or, if necessary, filtered or separated by any known method from the impure soap. The purified coloring-matter is precipitated by dilute hydrochloric or sulphuric or any suitable acid, this precipitation being effected when the liquor is either hot or cold. The

' coloring-matter separates sharply from the the cotton-seed oil at diiferent seasons of the year.

We claim- 1. The method of obtaining coloring-matter from cotton-seed oil, consisting in treating fractional precipitation, producing an insoluthe oil with an alkaline solution, separating ble soap from the fatty acids and other imthe solution from the oil, treating said solupurities, and precipitating the coloring-mattion to remove the impurities, and then preter from the remaining solution by an acid; 15 5 cipitating the coloring-matter from the resubstantially as described.

maining liquor by an acid; substantially as EDGAR SIDDONS WILSON described. i

2. The method of obtaining c01oring-matter EBENEZER STE WARrl' from cotton-seed oil, consisting in heating Witnesses: 10 the oil with an alkalinesolution, separating HENRY CUTHBERT STRIDE,

the resulting liquor, subjecting this liquor to SYDNEY GEORGE ANTHONY. 

